| Introduction to OOP | Chapter 10: Subclasses and Subtypes: | next | previous | audio | real | text |
It is extremely difficult to define meaning (think of the Stack ADT), and even if you can it is almost always impossible to determine if one class preserves the meaning of another.
One of the classic corollaries of the halting problem is that there is no procedure that can determine, in general, if two programs have equivalent behavior.